The present invention relates to a system for administering gas. More particularly, the present invention relates to a system for administering anesthesia/analgesia gas which provides convenient, direct access by a medical practitioner, a clear line of vision for the medical practitioner, and flexibility to accommodate the patient and medical professional's needs. The present invention also relates to a fluid control system for such a gas administering system and a method of operating the fluid control system.
N2O analgesia has been used for over a century to successfully relax and sedate dental patients. Originally and until recently the application of these gages was virtually unrestricted and thus the supply system required was relatively unencumbered. With the advent of mandatory scavenge systems for nitrous delivery, these units became much more bulky and difficult to use in day to day practice and this utilized rate declined.
Typically, the compressed medical gages are delivered to the practitioner's facility in gas cylinders. These cylinders either connect to a central distribution system, serving multiple operating rooms, or they are portable and are mounted on rolling carts which serve one operating room and patient. These cylinders are connected via hoses or piping to a regulating system which controls delivery pressure, flow rate and blended ratio. There are monitors, gages and other devices to provide information to the practitioner regarding the delivery parameters. From the control device, gas flows via flexible hoses to a nasal delivery interface device. As shown in FIG. 1, vacuum scavenging of expelled gases flows from the nasal delivery interface device, via flexible tubing, into the centralized building vacuum utility system.
These essential components are incorporated into support systems. Systems commonly found in the art fall into three general categories: a) cart mounted tanks and controls, b) cart mounted controls and c) wall or stationary cabinet mounted controls.
Cart mounted tanks and control systems utilize an open or closed, wheeled cart. (FIGS. 4, 9). Portable O2 and N2O tanks are mounted on the cart. The control system and breather bag are usually mounted on a center pole attached to an open cart or supported by the shell of an enclosed cart. The patient supply tubing connects the cart outlet to the nasal delivery interface device. Referring to FIG. 2, the scavenging tubing connects the nasal delivery interface device via flexible tubing into the centralized building vacuum utility system.
As illustrated in FIGS. 1-2, current systems running from the control devices to the nasal delivery interface device use multi lumen hose systems which are long, heavy, complex and somewhat stiff. They pull on the patient's head and limit practitioner accessibility to the patient's mouth area. As a result they also limit the ability of the practitioner to reposition the patient's head.
FIG. 1 shows a generic nitrous oxide anaesthetic administration system having a N2O and scavenging nasal shell 3, 4; a N2O and scavenging tubing 5; a breather bag connection and emergency air intake assembly 6; an intermediate N2O connection 7; a scavenge vacuum tube 8; a N2O tube 9; a N2O tube connector 10; N2O and scavenging tubing connectors 11; a scavenge vacuum tube connector 12; a breather bag 13; and a scavenging vacuum tube holder 16.
Cart mounted control systems are similar to those above, except that the 02 and N2O are supplied from a central source via floor or wall gas outlets rather than from in situ tanks. Flexible hoses route the gases from the outlet to the control system. The control system and breather bag are mounted on a center pole attached to an open, wheeled cart. The patient supply tubing connects the cart outlet to the nasal delivery interface device. The scavenging tubing connects the nasal delivery interface device via flexible tubing into the centralized building vacuum utility system.
As illustrated in FIG. 3, wall and cabinet mounted systems have the O2 and N2O gas supplied via flexible or rigid tubing from a central source. This tubing is enclosed in the walls of the operatory with other centralized utilities. The control system and breather bag are mounted to the wall or cabinet unit. The mounting may be a flush mount, surface or articulated arm mount design. Long patient supply tubing connects the control systems to the nasal delivery interface device on the patient. Long scavenging system tubing connects the nasal delivery interface device into the centralized building vacuum utility system.
Also, wall mounted systems are typically separated from the patient chair by a work surface or passageway. Wall mount systems have long hose lengths between the control devices and the nasal delivery interface device. The longer the hose length, the longer the latency period between changing a control setting and the patient actually receiving that changed gaseous output. In addition, the hose position and length interferes with operator positioning. Tubing runs from the wall mounted, control system outlet to the nasal delivery interface device. This tubing crosses a passageway or work surface and blocks or encumbers which ever of these it traverses.
As illustrated in FIGS. 4-8, cart mounted systems can be located behind one of the practitioners or tucked under the back of the patient chair. In either case, visual monitoring of critical information in impeded. This is a dangerous situation because unknown changes occurring in the gaseous anesthetic system can be detrimental to the patient. Additionally, excess gas expelled into the operatory is harmful to the practitioners.
Also, carts located in the passageways, or workplace around the patient chair, cause inference as the practitioners move around the patient. Staff can trip over the carts and be injured and the flow of other technology and emergency access is impeded. As well as the cost of damaging an anesthetic system, rupturing any high pressure, 2000 psi, system can be very dangerous to all occupants of the operatory.
There are two main drawbacks of the systems describe above. First, current systems usually put the system controls out of direct reach of the medical professional when he/she is seated in normal treatment positions. This limitation is especially burdensome with wall mounted systems. This makes it difficult for the medical professional to accomplish anesthetic system adjustments without walking around or reaching around the patient. This awkward arrangement slows access and response to emergency situations. Second, current systems often put monitoring device displays and gauges out of direct view of the doctor and assistant.
Therefore, it would be particularly desirable to provide a system or method for anesthesia/analgesia gas delivery provides a nitrous oxide anesthetic administration system which provides convenient, direct access by a medical practitioner, a clear line of vision for the medical practitioner, and flexible to accommodate the patient and professional's needs. Currently, there is no known nitrous oxide anesthetic administration system in the prior art which provides these benefits.